I search for solutions in this order: Past Code, Unreal Source, Wiki, BUF, groups.yahoo, google, screaming at monitor. – RegularX

From Unreal Wiki, The Unreal Engine Documentation Site

This zone kills pawns within it when triggered, and optionally changes their fatness and viewfog.

Some weirdness to note:

• default fatness is 128. Set DieFatness to smaller for thinning, larger for fattening but note that 0 doesn't work.
• viewfog is odd: it's a colour but defined by a vector. AFAIK it's taken as XYZ = RGB, with values 0 to 1.0
• The zone must be triggered before it will affect the players inside it.

See Message Placeholder for information on setting the death message.